Glucoalyssin

Variation of glucosinolates on position orders of flower buds in turnip rape (Brassica rapa).[Pubmed:30174493]

Saudi J Biol Sci. 2017 Nov;24(7):1562-1566.

To glucosinolate (GSL) contents on flower buds depending on their position orders in turnip rape (Brassica rapa), three Japanese 'Nabana' cultivars such as cv. No. 21 (Brassica rapa, early type), cv. Husanohana (B. rapa, late type) and cv. Norin No. 20 (B. napus) were investigated using HPLC analysis. Ten GSLs including glucoraphanin, sinigrin, Glucoalyssin, napoleiferin, gluconapin, 4-hydroxyglucobrassicin, glucobrassicanapin, glucobrassicin, and gluconasturtiin were detected. Differences in individual and total GSL contents were found between two plant varieties, which are also depending on various developmental stages. Among the GSLs, gluconapin (mean 23.11 mumole/g dry weight (DW) and glucobrassicanapin (mean 13.41 mumole/g DW) documented the most abundant compounds and contributed average 39 and 27% of the total GSLs, but indolyl and aromatic GSLs together accounted >10% of the total GSLs. The presence of significant quantities of gluconapin in the cultivars should be studied more extensively, since the GSL is mainly responsible for the bitter taste.

Molecular characterization of glucosinolates and carotenoid biosynthetic genes in Chinese cabbage (Brassica rapa L. ssp. pekinensis).[Pubmed:29379360]

Saudi J Biol Sci. 2018 Jan;25(1):71-82.

The present study aimed to investigate the contents of glucosinolates (GSLs) and carotenoids in eleven varieties of Chinese cabbage in relation to the expression level of the important transcription factors. MS and HPLC analysis identified the presence of 13 GSLs (progoitrin, sinigrin, Glucoalyssin, gluconapoleiferin, gluconapin, glucocochlearin, glucobrassicanapin, glucoerucin, 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, neoglucobrassicin and gluconasturtiin) and four carotenoids (lutein, zeaxanthin, alpha-carotene and beta-carotene). GSL contents were varied among the different cabbage varieties. The total GSL content ranged from 2.7 to 57.88 mumol/g DW. The proportion of gluconapin (54%) and glucobrassicanapin (22%) was higher in all the varieties, respectively. Results documented the variation in total and individual carotenoid contents that have also been observed among different varieties; however, the total carotenoid contents ranged from 289.12 to 1001.41 mg kg(-1) DW (mean 467.66). Interestingly, the proportion of lutein (66.5) and beta-carotene (25.9) were higher than alpha-carotene (5.1) and zeaxanthin (2.5%). Consequently, the expression level of the regulatory gene, MYB28 was higher in 'K0648' and was directly proportional to GSL content. Similarly, the expression levels of 1-PSY were higher in 'K0112'; however, the expression levels of 2-ZDS, 3-LCYB, 4-LCYE, 5-CHXB and 7-NCED genes showed no significant difference. In addition, the correlation between GSL and carotenoid contents and gene expression level showed moderate significant difference in each Chinese cabbage.

Identification and Quantification of Glucosinolates in Kimchi by Liquid Chromatography-Electrospray Tandem Mass Spectrometry.[Pubmed:28298926]

Int J Anal Chem. 2017;2017:6753481.

A novel and simple method for detecting five glucosinolates (Glucoalyssin, gluconapin, glucobrassicanapin, glucobrassicin, and 4-methoxyglucobrassicin) in kimchi was developed using liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS). The chromatographic peaks of the five glucosinolates were successfully identified by comparing their retention times, mass spectra. The mobile phase was composed of A (acetonitrile) and B (water). As for glucosinolate, the relative quantities were found through sinigrin, and five different compounds that have not been previously discovered in kimchi were observed. Monitoring was carried out on the glucosinolate in 20 kimchis distributed in markets, and this study examined the various quality and quantity compositions of the five components. The Glucoalyssin content ranged from 0.00 to 7.07 mumol/g of day weight (DW), with an average content of 0.86 mumol/g of DW, whereas the gluconapin content ranged from 0.00 to 5.85 mumol/g of DW, with an average of 1.17 mumol/g of DW. The content of glucobrassicanapin varied between 0.00 and 11.87 mumol/g of DW (average = 3.03 mumol/g of DW), whereas that of glucobrassicin varied between 0.00 and 0.42 mumol/g of DW (average = 0.06 mumol/g of DW). The 4-methoxyglucobrassicin content ranged from 0.12 to 9.36 mumol/g of DW (average = 3.52 mumol/g of DW). A comparison of the contents revealed that, in most cases, the content of 4-methoxyglucobrassicin was the highest.

Development and validation of a liquid chromatography-tandem mass spectrometry method to determine intact glucosinolates in bee pollen.[Pubmed:26209770]

J Chromatogr B Analyt Technol Biomed Life Sci. 2015 Sep 1;1000:49-56.

A new method was developed to determine twelve intact-glucosinolates (GLSs) (glucoiberin, GIB; glucoraphanin, GRA; glucoerucin GER; gluconapin, GNA; glucotropaeolin, GTL; glucobrassicin, GBC; gluconasturtiin, NAS; Glucoalyssin, ALY; 4-hydroxyglucobrassicin, 4OH; 4-methoxyglucobrassicin, 4ME; neoglucobrassicin, NEO; sinigrin, SIN) in bee pollen, by means of liquid chromatography tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI). An efficient extraction procedure was proposed (average analyte recoveries were between 85% and 96%); this involved a solid-liquid extraction (SLE) with heated water, followed by a solid phase extraction (SPE) with a weak anion exchange (NH2) sorbent. Chromatography was performed on a Gemini((R)) C18 analytical column with a mobile phase of formic acid in water (0.5%,v/v) and formic acid in acetonitrile (0.5%,v/v), in gradient elution mode at 1mL/min, resulted in baseline-separated peaks and a run time of 30min. The method was fully validated in terms of selectivity, limits of detection (LOD) and quantification (LOQ), linearity, carry-over effect, reinjection reproducibility, precision and accuracy. A good selectivity, low LODs and LOQs, ranging from 1 to 16mug/kg, wide linear ranges from LOQ to 1000mug/kg, and satisfactory reinjection reproducibility, precision and accuracy with relative standard deviation and relative error values lower than or equal to 9%; meanwhile, results indicates a negligible carry-over effect. The proposed method was applied to analyze intact-GLSs in bee pollen. Nine of the GLSs studied were identified in certain samples analyzed over a wide concentration range (LOQ-2226mug/kg), and significant differences in GLS content were observed among the samples.

Variation of glucosinolate accumulation and gene expression of transcription factors at different stages of Chinese cabbage seedlings under light and dark conditions.[Pubmed:24868877]

Nat Prod Commun. 2014 Apr;9(4):533-7.

Chinese cabbage is one of the most important leafy vegetables widely used in East Asian cuisines. The glucosinolate (GSL) accumulation and transcript levels of 7 transcription factors (Dof1.1, IQD1-1, MYB28, MYB29, MYB34, MYB51, and MYB122, and their isoforms) involved in the biosynthesis of aliphatic and indolic glucosinolates (GSLs) were analyzed at different stages of Chinese cabbage (Brassica rapa ssp. pekinensis) seedlings under light and dark conditions using high performance liquid chromatography and quantitative real time PCR. During seedling development, transcription of almost all transcription factors under light conditions was higher expressed than under dark conditions. Five aliphatic GSLs (progoitrin, sinigrin, Glucoalyssin, gluconapin, and glucobrassicanapin) and four indolic GSLs (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrasscin) were detected. Total GSL contents under light conditions 6, 8, and 10 days after sowing (DAS) were 3.2-, 3.9-, and 6.9-fold higher, respectively than those of dark conditions. Interestingly, total GSL contents 2 {85.4 micromol/g dry weight (DW)} to 10 (7.74 micromol/g DW) DAS under dark conditions were gradually decreased. In this study, our results suggest that light affects the levels of GSL in Chinese cabbage seedlings. These results could be useful for obtaining cabbage varieties rich in GSLs.

Optimized extraction, separation and quantification of twelve intact glucosinolates in broccoli leaves.[Pubmed:24444907]

Food Chem. 2014;152:66-74.

A new method has been developed and validated to determine twelve intact glucosinolates (glucoiberin, GIB; glucoraphanin, GRA; glucoerucin GER; gluconapin, GNA; glucotropaeolin, GTL; glucobrassicin, GBC; gluconasturtiin, GST; Glucoalyssin, ALY; 4-hydroxyglucobrassicin, 4-OH; 4-metoxyglucobrassicin, 4ME; neoglucobrassicin, NEO; sinigrin, SIN) in broccoli leaves using liquid chromatography (LC) coupled to diode array (DAD) and electrospray ionization mass spectrometry (ESI-MS) detection. An extraction procedure has also been proposed and optimized by means of statistical analysis (the Box-Behnken design and analysis of variance); this is based on the deactivation of myrosinase using a microwave and heated water. Low limits of detection and quantification were obtained, ranging from 10 to 72 mug/g with DAD and 0.01 to 0.23 mug/g with ESI-MS, and the resulting recovery values ranged from 87% to 106% in all cases. Finally, glucosinolates were analyzed in broccoli leaf samples from six different cultivars (Ramoso calabrese Parthenon, Marathon, Nubia, Naxos and Viola).

Glucosinolates in two endemic plants of the Aurinia genus and their chemotaxonomic significance.[Pubmed:24354202]

Nat Prod Commun. 2013 Oct;8(10):1463-6.

Glucosinolates (GLs) were characterized in the seed and root of Aurinia leucadea (Guss.) C. Koch and A. sinuata (L.) Griseb., and quantified according to the ISO 9167-1 official method based on the HPLC analysis of desulfo-GLs. Glucoalyssin (GAL, 1), glucobrassicanapin (GBN, 2) and glucoberteroin (GBE, 3) were the major GLs identified in A. leucadea and A. sinuata. GC/MS analysis of the volatile fractions obtained after enzyme hydrolysis showed that they mostly contain isothiocyanates (ITCs) originating from the parent GLs. On this basis and from previous reports, C-5 alkyl GLs 1, 2, and 3 can be considered as chemotaxonomic markers of the Aurinia genus.

MYB transcription factors regulate glucosinolate biosynthesis in different organs of Chinese cabbage (Brassica rapa ssp. pekinensis).[Pubmed:23881053]

Molecules. 2013 Jul 22;18(7):8682-95.

In this study, we investigated the expression of seven MYB transcription factors (a total of 17 genes that included Dof1.1, IQD1-1, MYB28, MYB29, MYB34, MYB51, and MYB122 and their isoforms) involved in aliphatic and indolic glucosinolate (GSL) biosynthesis and analyzed the aliphatic and indolic GSL content in different organs of Chinese cabbage (Brassica rapassp. Pekinensis). MYB28 and MYB29 expression in the stem was dramatically different when compared with the levels in the other organs. MYB34, MYB122, MYB51, Dof1.1, and IQD1-1 showed very low transcript levels among different organs. HPLC analysis showed that the glucosinolates (GSLs) consisted of five aliphatic GSLs (progoitrin, sinigrin, Glucoalyssin, gluconapin, and glucobrassicanapin) and four indolic GSLs (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxygluco-brassicin, and neoglucobrassicin). Aliphatic GSLs exhibited 63.3% of the total GSLs content, followed by aromatic GSL (19.0%), indolic GSLs (10%), and unknown GSLs (7.7%) in different organs of Chinese cabbage. The total GSL content of different parts (ranked in descending order) was as follows: seed > flower > young leaves > stem > root > old leaves. The relationship between GSLs accumulation and expression of GSLs biosynthesis MYB TFs genes in different organs may be helpful to understand the mechanism of MYB TFs regulating GSL biosynthesis in Chinese cabbage.

Homoeologous GSL-ELONG gene replacement for manipulation of aliphatic glucosinolates in Brassica rapa L. by marker assisted selection.[Pubmed:23532458]

Front Plant Sci. 2013 Mar 25;4:55.

Aliphatic glucosinolates are the predominant sulfur-rich plant secondary metabolites in economically important Brassica crops. Glucosinolates and their hydrolysis products are involved in plant-microbe, plant-insect, plant-animal, and plant-human interactions. It is, therefore, important to manipulate glucosinolate profiles and contents in Brassica species. In this study, aliphatic glucosinolates were genetically manipulated through homoeologous recombination in backcross lines followed by marker assisted selection in B. rapa. A resynthesized B. napus line, from a cross between B. rapa and B. oleracea, was backcrossed with Chinese cabbage doubled haploid line, RI16. Marker assisted selection for non-functional gene was performed in each backcross generations. Advanced backcross progenies (BC3F2) were developed to identify homoeologous gene replacement and/or introgression. Reduction in 5C aliphatic glucosinolates (gluconapoleiferin, Glucoalyssin, and glucobrassicanapin) was observed in BC3F2 progenies of the recurrent parent that carried the GSL-ELONG (-) gene. The GSL-ELONG (-) positive backcross progenies were also screened by the A-genome and BraGSL-ELONG gene specific marker, which linked with 5C aliphatic glucosinolates. The A-genome specific marker was absent in the plants of advanced backcross progenies which showed reduction in 5C aliphatic glucosinolates. The results suggest that the functional allele had been replaced by the non-functional GSL-ELONG (-) allele from B. oleracea. Some advanced backcross progenies (BC3F2) positive for the GSL-ELONG (-) allele and the A-genome specific SCAR marker BraMAM1-1 did not show reduction in 5C aliphatic glucosinolates, suggesting that GSL-ELONG (-) allele is recessive. Replacement of the functional locus in the A-genome by non-functional counterpart in the C-genome reduced the content of 5C aliphatic glucosinolates in B. rapa seeds with 20 mumol/g.

Glucosinolate profiling and antimicrobial screening of Aurinia leucadea (Brassicaceae).[Pubmed:22162169]

Chem Biodivers. 2011 Dec;8(12):2310-21.

Glucosinolates (GLs) were characterized in various aerial parts (stems, leaves, and flowers) of Aurinia leucadea (Guss.) C. Koch and quantified according to the ISO 9167-1 official method based on the HPLC analysis of desulfoglucosinolates. Eight GLs, i.e., glucoraphanin (GRA), Glucoalyssin (GAL; 1), gluconapin (GNA; 2), glucocochlearin (GCC), glucobrassicanapin (GBN; 3), glucotropaeolin (GTL), glucoerucin (GER), and glucoberteroin (GBE) were identified. The total GL contents were 57.1, 37.8, and 81.3 mumol/g dry weight in the stems, leaves, and flowers, respectively. The major GL detected in all parts of the plant was 2, followed by 1 and 3. GC/MS Analysis of the volatile fractions extracted from the aerial parts of fresh plant material either by hydrodistillation or CH(2) Cl(2) extraction showed that these fractions mostly contained isothiocyanates (ITCs). The main ITCs were but-3-enyl- (55.6-71.8%), pent-4-enyl- (7.6-15.3%), and 5-(methylsulfinyl)pentyl ITC (0-9.5%), originating from the corresponding GLs 2, 3, and 1, respectively. The antimicrobial activity of the volatile samples was investigated by determining inhibition zones with the disk-diffusion method and minimal inhibitory concentrations (MIC) with the microdilution method. They were found to inhibit a wide range of bacteria and fungi, with MIC values of 2.0-32.0 mug/ml, indicating their promising antimicrobial potential, especially against the fungi Candida albicans and Rhizopus stolonifer as well as against the clinically important pathogen Pseudomonas aeruginosa.

Glucosinolate distribution in aerial parts of Degenia velebitica.[Pubmed:22083920]

Chem Biodivers. 2011 Nov;8(11):2090-6.

The glucosinolates present in the leaf, stem, and seed extracts of Degenia velebitica (Degen) Hayek were characterized and quantified according to the ISO 9167-1 method, which is based on the HPLC analysis of desulfoglucosinolates. The stems contained Glucoalyssin (3a) as the major compound as well as glucoberteroin (1a) and glucoaubrietin (4a). The leaves contained three glucosinolates, the major one being 3a, followed by glucobrassicanapin (2a) and 1a. Glucoberteroin (1a) was the major glucosinolate in the seeds, along with the two minor glucosinolates 3a and glucoerucin (5a). The content of 1a in the whole, non-defatted seeds amounted to 4% (w/w). The compound was characterized as its desulfo counterpart by spectroscopic techniques.

Rocket salad (Diplotaxis and Eruca spp.) sensory analysis and relation with glucosinolate and phenolic content.[Pubmed:21725983]

J Sci Food Agric. 2011 Dec;91(15):2858-64.

BACKGROUND: Salad crops of the Brassicaceae family, such as Diplotaxis tenuifolia and Eruca vesicaria, commonly referred to as 'rocket salads', have attracted considerable interest as culinary vegetables because of their strong flavour and their content of putative health-promoting compounds. Among such compounds, glucosinolates and phenolics are well-known phytochemicals with an important role also in determining the characteristic flavour of these species. In this study, to identify potentially high-value rocket salads, 37 cultivated types were examined for sensory characters and their relations with glucosinolate and phenolic contents, which ranged from 0.76 to 3.03 g kg(-1) dry weight (DW) and from 4.68 to 31.39 g kg(-1) DW, respectively. RESULTS: The perception of bitter taste was significantly affected by specific glucosinolates, namely progoitrin/epiprogoitrin and dimeric glucosativin. Aroma intensity was negatively related to Glucoalyssin content, whereas pungency was significantly related to total glucosinolate content. Kaempferol-3-(2-sinapoyl-glucoside)-4'-glucoside was positively and significantly related to all flavour trait perceptions. Aroma intensity, pungency, crunchiness and juiciness were positively related to typical rocket salad flavour perception through a prominent direct effect. CONCLUSION: Aroma intensity, pungency, crunchiness and juiciness were strong determinants of overall rocket salad flavour perception. Visual traits also characterised sensory components. Bitterness, usually considered a negative flavour trait, was moderately perceived in the examined material, without negatively affecting typical flavour perception. In the range of the examined material, glucosinolate content did not contrast with typical flavour, demonstrating that good taste and putative health-promoting properties may coexist.

Variation of glucosinolates in vegetable crops of Brassica rapa.[Pubmed:17187832]

Phytochemistry. 2007 Feb;68(4):536-45.

Glucosinolate levels in leaves were determined in a collection of 113 varieties of turnip greens (Brassica rapa L.) from northwestern Spain grown at two sites. Sensorial attributes were also assessed by a consumer panel. The objectives were to determine the diversity among varieties in total glucosinolate content and glucosinolate profile and to evaluate their sensory attributes in relation to glucosinolate content for breeding purposes. Sixteen glucosinolates were identified, being the aliphatic glucosinolates, gluconapin and glucobrassicanapin the most abundant. Other aliphatic glucosinolates, such as progoitrin, Glucoalyssin, and gluconapoleiferin were relatively abundant in varieties with a different glucosinolate profile. Indolic and aromatic glucosinolate concentrations were low and showed few differences among varieties. Differences in total glucosinolate content, glucosinolate profile and bitterness were found among varieties, with a total glucosinolate content ranging from 11.8 to 74.0micromolg(-1) dw at one site and from 7.5 to 56.9micromolg(-1) dw at the other site. Sensory analysis comparing bitterness with variation in glucosinolate, gluconapin and glucobrassicanapin concentrations suggested that these compounds and their breakdown products are not the only determinants of the characteristic flavour of this vegetable. Other phytochemicals are probably involved on the characteristic bitter flavour. The varieties MBG-BRS0132, MBG-BRS0082, MBG-BRS0173, and MBG-BRS0184 could be good candidates for future breeding programs since they had high total glucosinolate content and good agronomic performance. The presence of glucoraphanin in some varieties should be studied more extensively, because this aliphatic glucosinolate is the precursor of sulforaphane, a potent anti-cancer isothiocyanate.

Analysis of glucosinolates, isothiocyanates, and amine degradation products in vegetable extracts and blood plasma by LC-MS/MS.[Pubmed:16289008]

Anal Biochem. 2005 Dec 15;347(2):234-43.

Dietary glucosinolates are under intensive investigation as precursors of cancer-preventive isothiocyanates. Quantitation of the dose and bioavailability of glucosinolates and isothiocyanates requires a comprehensive analysis of the major dietary glucosinolates, isothiocyanates, and related metabolites. We report a liquid chromatography with tandem mass spectrometric detection (LC-MS/MS) analytical method for the comprehensive analysis of the seven major dietary glucosinolates, related isothiocyanates, and putative amine degradation products. The parent glucosinolates were sinigrin, gluconapin, progoitrin, glucoiberin, glucoraphanin, Glucoalyssin, and gluconasturtiin. The LC-MS/MS analysis method for these compounds was developed and validated; a standard addition analysis protocol was used generally to avoid the requirement for stable isotopic standards. Where stable isotopic standards were available, internal standardization with these gave estimates in agreement with those obtained by the standard addition analysis protocol. For glucosinolates, negative ion electrospray LC-MS/MS analysis was performed. Isothiocyanates and amines were prederivatized to the corresponding thiourea and N-acetamides, respectively, and were quantified by positive ion electrospray LC-MS/MS. The limits of detection were 0.5-2 pmol; the recoveries for glucosinolates, isothiocyanates, and amines were 85-90%, 50-85%, and 60-70%, respectively; and the intra- and interbatch coefficients of variation were 1-4% and 3-10%, respectively. These methods provide facile access to comprehensive analytical data on the major dietary glucosinolates and related metabolites to quantify inputs and metabolic formation of these compounds in cancer prevention and related studies.